From nobody Wed Feb 11 06:31:30 2026 Received: from out30-100.freemail.mail.aliyun.com (out30-100.freemail.mail.aliyun.com [115.124.30.100]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 385563D556 for ; Wed, 21 Feb 2024 09:28:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.100 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708507692; cv=none; b=I45oBCvl+XBPXOHK/Vv9n4xd6GwCOC5OB9fv+I4/4fqPTIl11NUZKweSlETKygE+RECljTXSae7p9aO2NRwm3f6yssGivnFHp0AtFJ77Kx8RzaSb5suIe5c9y2XirOF5x9c9nUKAyqhv2fD3OcsJP6zi1tBr/b+bl+Lv3raiqw8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708507692; c=relaxed/simple; bh=x2riKMYmISimOeooDuvtdgn5hEARkXgRbBvuG4j/oVE=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=K5njrrUZFu41YuUz+xE7cC411/Y/93OgTuPToE9ZWjvWgq9A+pPuRCo19TTc0+AqzbdMkexDWx5b6JMBbv5pLZnB3/8r2S9dfUUsfvkgQqJcG6EUEMWsjSSa92RTnFYmqTp+tMSREalNU5MsX1Sy3E4WZDkq0eqxfpI8tx2H6ao= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=tbf261B3; arc=none smtp.client-ip=115.124.30.100 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="tbf261B3" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1708507687; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=m3nqGI/fMVZjL40459w/MnS9DkbLdhc8HEWPtY+H0PM=; b=tbf261B3zP1aJ8GoO26ZLScrCldl7dzZMaMeJlr4A0bIl/eqetArzNNTiOsFE+fOf/P1yNqrhbc01ou4qQRZMWJoVnjJ3soxij/rRObHr6LyXu5wk8ViEdZ/Bm1Q1GVHnL3JyQopwO4VLGTofhfHTP+Uxm8md5XHJXiDpx/ZCk0= X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R101e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046050;MF=baolin.wang@linux.alibaba.com;NM=1;PH=DS;RN=10;SR=0;TI=SMTPD_---0W0zShrU_1708507686; Received: from localhost(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0W0zShrU_1708507686) by smtp.aliyun-inc.com; Wed, 21 Feb 2024 17:28:06 +0800 From: Baolin Wang To: akpm@linux-foundation.org Cc: muchun.song@linux.dev, osalvador@suse.de, david@redhat.com, linmiaohe@huawei.com, naoya.horiguchi@nec.com, mhocko@kernel.org, baolin.wang@linux.alibaba.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH 3/3] docs: hugetlbpage.rst: add hugetlb migration description Date: Wed, 21 Feb 2024 17:27:55 +0800 Message-Id: <75b80937a84bd98211cea0607707bfdee8cb5873.1708507022.git.baolin.wang@linux.alibaba.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add some description of the hugetlb migration strategy. Signed-off-by: Baolin Wang --- Documentation/admin-guide/mm/hugetlbpage.rst | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/Documentation/admin-guide/mm/hugetlbpage.rst b/Documentation/a= dmin-guide/mm/hugetlbpage.rst index e4d4b4a8dc97..68d7bc2165c9 100644 --- a/Documentation/admin-guide/mm/hugetlbpage.rst +++ b/Documentation/admin-guide/mm/hugetlbpage.rst @@ -376,6 +376,13 @@ Note that the number of overcommit and reserve pages r= emain global quantities, as we don't know until fault time, when the faulting task's mempolicy is applied, from which node the huge page allocation will be attempted. =20 +The hugetlb may be migrated between the per-node hugepages pool in the fol= lowing +scenarios: memory offline, memory failure, longterm pinning, syscalls(mbin= d, +migrate_pages, move_pages), alloc_contig_range() and alloc_contig_pages().= Now +only memory offline, memory failure and syscalls allow fallback to allocat= e a +new hugetlb on a different node if the current node is unable to allocate = during +hugetlb migration, that means these 3 cases can break the per-node hugepag= es pool. + .. _using_huge_pages: =20 Using Huge Pages --=20 2.39.3